Can Air Quality in a Car Be Better Than at Home During Wildfire Smoke?

During the June 2023 Canadian wildfire smoke event, we noticed something unexpected while driving the Range Rover P400: the car’s cabin air-quality reading dropped far below the outdoor reading after the climate system had been running for a few minutes.

What we observed in the Range Rover

During that smoke event, the outside air-quality reading was extremely poor, while the in-cabin display showed a much lower particulate reading after the vehicle had been running. That was an interesting real-world observation, but it should not be interpreted as proof that a car is always safer than a home or that every vehicle will achieve the same result.

Why a car cabin can sometimes have cleaner air

Vehicle cabins can reduce smoke exposure when windows are closed and the climate system is set to recirculate. The EPA specifically recommends closing vehicle windows and using recirculation mode during wildfire smoke because it reduces the amount of smoky outside air being pulled into the cabin.

How well that works depends on the vehicle, cabin filter, ventilation settings, how often doors are opened, and how severe the outdoor smoke is.

Why a home may still be the better place to stay

A properly sealed and filtered home can also provide much cleaner air than outdoors. The EPA recommends closing windows and doors, using recirculation where appropriate, running a high-efficiency HVAC filter such as MERV 13 when the system can support it, and using a properly sized portable air cleaner.

So the lesson from our 2023 drive was not “cars have better air than houses.” It was that filtration and recirculation matter, whether you are in a vehicle or at home.

What to do during wildfire smoke

Check current air-quality conditions, keep windows closed when smoke is heavy, reduce outdoor activity, and use recirculation and filtration where available. If you are driving, the EPA recommends running the air conditioner in recirculate mode to reduce smoke entering the vehicle.

This reflects one specific observation in a Range Rover P400 during the June 2023 Canadian wildfire smoke event. Air-quality conditions, vehicle filtration performance, and public-health guidance can vary by event.

For more on the vehicle itself, read our Range Rover P400 review.